Did Mechanics break my TPMS?

Question

Preface, I have a 2009 Honda Fit Sport, bought used last year from a reputable dealer. I'm clueless about car things, and had the same mechanic for 15 years. But he recently disappeared, so i had to go somewhere new, and fast, to get my insurance squared away this year.

So I went for a routine inspection at a local place (that has a 4.8 star rating, for what that's worth). This guy said my back tires were balding and would fail inspection, he heavily implied that if i got my tires done by someone else, that it would interfere with my obtaining an inspection in due time, or some such business. so i gave him 300 bucks and, despite feeling a little railroaded, was generally happy to have new tires.

Except after that, maybe a week later, my tire light kept on going on, it seemed like the back tires had a slow leak that i would have to refill once a week, which was discouraging. I put it off because the idea of confronting them made me feel anxious, but eventually i made my way back to them and found the courage to ask what went wrong.

They said the tpms valves (right word/term?) were causing a leak, but it wasn't their fault. I asked why they would both break at the same time as their tire change, they said they must have both been so corroded that any tire change would have broken them. They then said it would be 75 dollars each to fix. I must have really gaped at them because they then said, maybe they could fix them for less, they would have to look.

While bringing me back to my car, they showed me two random TPMS valves, one with a broken seal, and one with a hairline crack in the metal. He then said, you know, its where we live, these things are bound to happen. because we live in new england, things corrode ( i am not near a coast or anything, im in Blackstone, MA)

After i was driving away i realized i deeply wish i could have mentioned to them that i had my front two tires replaced just weeks before the back ones, and they are functioning perfectly, why would both the back be so fragile, and both the front be fine?

So, is corrosion a credible excuse? Is this a common occurrence?

Answer 1

Your first major red flag is "you'll fail inspection, but if you let us fix your car RIGHT NOW you'll get your sticker!"

All joking aside (not so much a joke..), it's unlikely these would both go bad. I have a 2007 vehicle that has original valve stems with no corrosion/rot at all (not garaged, I'm in Natick). It's quite possible they just threw the rims up on the tire changer and beat the you know what out of them. These gas station mechanics in MA are (generally) not to be trusted. Inspection stickers are a HUGE source of income for them since you are at their mercy. Next time take the rejection sticker and shop around. When you go back with an invoice that the work was done by someone reputable, they cannot fail you.

A sure sign of mechanic carelessness would be scuffed up rims if they were in perfect shape prior to arriving at the shop... and do NOT pay $75 a piece to replace valve stems! Outrageous. It's unfortunate this happens all the time.

Answer 2

It depends on where the valve was leaking from. I would of asked to see the old TPM units if that's not what they showed you.

If it was leaking around the schrader valve, it's possible they didn't replace the valve with a new one. This won't necessarily cause a leak but if the neoprene seal on the valve is damaged it can leak. It's also possible that the threads the valve screws into are corroded leading to a leak.

If it was leaking around where the stem seals to the wheel this is usually corrected by installing a new kit which includes a new seal, schader valve and aluminum nut. This is not a replacement of the whole unit. Generally these kits are sold as part of the tire service as they're considered wear items.

As to the hairline crack it's unlikely they would of damaged the stem during installation. Usually when tires are mounted improperly the sensor portion will break away from the stem. Due to the sensor having a plastic enclosure and the stem being made from aluminum in your case.

Answer 3

General advice about tires with TPMS sensors: you want to replace all sensors at the same time you replace tires, and you don't want to use off-brand parts.

99% of tire shops that are not specialized to a certain brand of vehicle, but rather do work for all brands, use cheap off-brand sensors, except maybe it's possible that some shop doesn't replace the sensors at all. These shops should be avoided.

It's likely that the sensors were somehow broken during tire installation. However, those should have been changed. The sensors have a battery that has a finite life, and in most cases the battery isn't replaceable. Therefore, you want the sensors changed because if they aren't changed, the battery will eventually run out and you have a TPMS light on.

I suspect the replacement sensors they installed are not Honda sensors but cheap off-brand sensors. These are likely to cause problems in the long run.

Also, when sensors are changed with brand name parts, you need to change the sensor id:s in the car's memory. If you have two sets of wheels (summer and winter) and the car's memory has two sets of sensors programmed, if you have summer wheels on but are requesting winter tires to be changed, it's possible an independent tire shop doesn't even think about reprogramming the inactive sensor id:s for the other set of wheels in the car's memory. Doing this at a Honda shop is less likely to cause problems when you finally install the winter wheels the next time.

You had poor service at least once (replacing tires without replacing sensors), maybe twice (it's possible the installed sensors installed are cheap off-brand units that could cause problems in the long run).

When repairing a puncture, in that case it's ok to use an old sensor (so it's ok to use any generic tire shop). The reason being that puncture repair is a short-term repair and you will replace the broken tire anyway at some point of time soon when the other 3 tires are replaced too, so a sensor swap during puncture repairs isn't necessary.